Morphological Variability of Sphenoid Sinus Pneumatization and Its Impact on Adjacent Neurovascular Structures
Abstract
1. Introduction
2. Materials and Methods
2.1. Sample Demographics
2.2. Radiological Protocol
2.3. Methodology
- Agenesis—absence of the SS;
- Conchal—slight pneumatization; sinus does not reach the anterior sellar wall and terminates ≥10 mm anterior to it;
- Presellar—pneumatization limited to the vertical plane of the anterior sellar wall;
- Sellar incomplete—pneumatization reaches the vertical plane of the posterior clinoid process, involving the anterior wall and sellar floor;
- Sellar complete—pneumatization extends beyond the sella toward the basilar occiput.
- Anterior extension (axial): pneumatization extending anteriorly beyond a line drawn along the sinus side of the sphenoid crest.
- Posterior (clival) extension (sagittal): subtypes—subdorsal, dorsal, occipital, and combined (dorsal + occipital)—defined relative to the posterior sellar wall, sellar floor line, and the horizontal plane through the superior margins of the paired Vidian canals.
- Lateral extension (coronal): presence of pneumatization lateral to the SS categorized as LW, GW, PP, full-lateral (GW + PP), and combinations thereof.
2.4. Statistical Analysis
3. Results
3.1. Sphenoid Sinus Pneumatization—Main Types
3.2. Sphenoid Sinus Pneumatization—Extension Patterns
3.3. Adjacent Neurovascular Structures
3.4. Association Between Sphenoid Sinus Pneumatization Types and Adjacent Neurovascular Structures
4. Discussion
4.1. Anatomical Considerations of Sphenoid Sinus Pneumatization (SSP)
4.2. Anatomical Considerations of Neurovascular Relationships
4.3. Surgical Significance of Morphological Variations
4.4. Strengths and Limitations
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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| SS Main Types | Total (n = 253) | Females (n = 124) | Males (n = 129) | p-Value | Age Distribution | p-Value |
|---|---|---|---|---|---|---|
| Sellar Complete | 160 (63.2%) | 81 (65.3%) | 79 (61.2%) | 0.288 | 50.46 (14.6) | 0.634 |
| Sellar Incomplete | 70 (27.7%) | 33 (26.6%) | 37 (28.7%) | 53.63 (15.8) | ||
| Presellar | 22 (8.7%) | 9 (7.3%) | 13 (10.1%) | 54.14 (14.8) | ||
| Agenesis † | 1 (0.4%) | 1 (0.8%) | 0 (0%) | 70.00 (-) |
| SSP Extension Patterns | Total (n = 506) | Left (n = 253) | Right (n = 253) | p-Value | Females (n = 248) | Males (n = 258) | p-Value |
|---|---|---|---|---|---|---|---|
| Anterior | 102 (20.2%) | 52 (20.6%) | 50 (19.8%) | 0.825 | 42 (16.9%) | 60 (23.3%) | 0.076 |
| Lateral | 236 (46.6%) | 121 (47.8%) | 115 (45.5%) | 0.366 | 117 (47.2%) | 119 (46.1%) | 0.184 |
| LW | 35 (6.9%) | 13 (5.1%) | 22 (8.7%) | 11 (4.4%) | 24 (9.3%) | ||
| GW | 56 (11.1%) | 34 (13.4%) | 22 (8.7%) | 31 (12.5%) | 25 (9.7%) | ||
| PP | 23 (4.5%) | 10 (4%) | 13 (5.1%) | 14 (5.6%) | 9 (3.5%) | ||
| FL | 58 (11.5%) | 29 (11.5%) | 29 (11.5%) | 33 (13.3%) | 25 (9.7%) | ||
| LW + GW | 11 (2.2%) | 5 (2%) | 6 (2.4%) | 6 (2.4%) | 5 (1.9%) | ||
| LW + PP | 5 (1%) | 4 (1.6%) | 1 (0.4%) | 3 (1.2%) | 2 (0.8%) | ||
| LW + FL | 48 (9.5%) | 26 (10.3%) | 22 (8.7%) | 19 (7.7%) | 29 (11.2%) | ||
| Posterior | 161 (63.6%) | - | - | - | 81 (65.3%) | 80 (62%) | <0.001 * |
| Dorsal | 16 (6.2%) | 3 (2.4%) | 13 (10.1%) | ||||
| Subdorsal | 136 (53.8%) | 73 (58.9%) | 63 (48.8%) | ||||
| Occipital | 7 (2.8%) | 5 (4%) | 2 (1.6%) | ||||
| Combination | 2 (0.8%) | 0 (0%) | 2 (1.6%) |
| Parameters | Total (n = 506) | Left (n = 253) | Right (n = 253) | p-Value | Females (n = 248) | Males (n = 258) | p-Value |
|---|---|---|---|---|---|---|---|
| ICA Pt | 103 (20.4%) | 52 (20.6%) | 51 (20.2%) | 0.728 | 42 (16.9%) | 61 (23.6%) | 0.139 |
| ICA Pt + Dh | 14 (2.8%) | 8 (3.2%) | 6 (2.4%) | 9 (3.6%) | 5 (1.9%) | ||
| ON Pt | 83 (16.4%) | 40 (15.8%) | 43 (17%) | 0.335 | 31 (12.5%) | 52 (20.2%) | 0.051 |
| ON Pt + Dh | 15 (3%) | 5 (2%) | 10 (4%) | 8 (3.2%) | 7 (2.7%) | ||
| VN Pt | 78 (15.4%) | 40 (15.8%) | 38 (15%) | 0.242 | 44 (16.9%) | 34 (13.2%) | 0.232 |
| VN Pt + Dh | 64 (12.6%) | 38 (15%) | 26 (10.3%) | 27 (10.9%) | 37 (14.3%) | ||
| MN Pt | 28 (5.5%) | 17 (6.7%) | 11 (4.3%) | 0.320 | 14 (5.6%) | 14 (5.4%) | 0.278 |
| MN Pt + Dh | 11 (2.2%) | 7 (2.8%) | 4 (1.6%) | 8 (3.2%) | 3 (1.2%) |
| Pneumatization Types | ICA | ON | VN | MN | p-Value | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Typical (n = 389) | Pt/Pt + Dh (n = 117) | Typical (n = 408) | Pt/Pt + Dh (n = 98) | Typical (n = 364) | Pt/Pt + Dh (n = 142) | Typical (n = 467) | Pt/Pt + Dh (n = 39) | |||
| Main | Aplasia | 2 (100%) | 0 (0%) | 2 (100%) | 0 (0%) | 2 (100%) | 0 (0%) | 2 (100%) | 0 (0%) | <0.001 * |
| Conchal | ND | ND | ND | ND | ND | ND | ND | ND | ||
| Presellar | 41 (93.2%) | 3 (6.8%) | 41 (93.2%) | 3 (6.8%) | 44 (100%) | 0 (0%) | 44 (100%) | 0 (0%) | ||
| SI | 137 (99.3%) | 1 (0.7%) | 129 (93.5%) | 9 (6.5%) | 127 (92%) | 11 (8%) | 136 (98.6%) | 2 (1.4%) | ||
| SC | 209 (64.9%) | 113 (35.1%) | 236 (73.3%) | 86 (26.7%) | 191 (59.4%) | 141 (40.6%) | 285 (88.5%) | 37 (11.5%) | ||
| Posterior Extension | Subdorsal | 192 (70.6%) | 80 (29.4%) | 208 (76.5%) | 64 (23.5%) | 171 (62.9%) | 101 (37.1%) | 246 (90.4%) | 26 (9.6%) | <0.001 * |
| Dorsal | 6 (18.8%) | 26 (81.2%) | 18 (56.3%) | 14 (43.7%) | 11 (34.4%) | 21 (65.6%) | 23 (71.9%) | 9 (28.1%) | ||
| Occipital | 9 (64.3%) | 5 (35.7%) | 9 (64.3%) | 5 (35.7%) | 7 (50%) | 7 (50%) | 12 (85.7%) | 2 (14.3%) | ||
| Combo | 2 (50%) | 2 (50%) | 1 (25%) | 3 (75%) | 2 (50%) | 2 (50%) | 4 (100%) | 0 (0%) | ||
| Lateral Extension | FL | 49 (46.2%) | 57 (53.8%) | 58 (54.7%) | 48 (45.3%) | 16 (15.1%) | 90 (79.9%) | 75 (70.8%) | 31 (29.2%) | <0.001 * |
| GW | 50 (74.6%) | 17 (25.4%) | 56 (83.6%) | 11 (16.4%) | 35 (52.2%) | 32 (47.8%) | 59 (88.1%) | 8 (11.9%) | ||
| PP | 18 (64.3%) | 10 (35.7%) | 23 (100%) | 0 (0%) | 12 (42.9%) | 16 (56.1%) | 28 (100%) | 0 (0%) | ||
| LW | 43 (43.4%) | 56 (56.6%) | 4 (4%) | 95 (96%) | 44 (44.4%) | 45 (55.6%) | 81 (81.8%) | 18 (18.2%) | ||
| Anterior Extension | Yes | 87 (85.3%) | 15 (14.7%) | 91 (89.2%) | 11 (10.8%) | 73 (71.6%) | 29 (28.4%) | 94 (92.2%) | 8 (7.8%) | >0.05 |
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Papadopoulos-Manolarakis, P.; Triantafyllou, G.; Georgalas, C.; Paschopoulos, I.; Stranjalis, G.; Piagkou, M. Morphological Variability of Sphenoid Sinus Pneumatization and Its Impact on Adjacent Neurovascular Structures. Diagnostics 2026, 16, 809. https://doi.org/10.3390/diagnostics16050809
Papadopoulos-Manolarakis P, Triantafyllou G, Georgalas C, Paschopoulos I, Stranjalis G, Piagkou M. Morphological Variability of Sphenoid Sinus Pneumatization and Its Impact on Adjacent Neurovascular Structures. Diagnostics. 2026; 16(5):809. https://doi.org/10.3390/diagnostics16050809
Chicago/Turabian StylePapadopoulos-Manolarakis, Panagiotis, George Triantafyllou, Christos Georgalas, Ioannis Paschopoulos, George Stranjalis, and Maria Piagkou. 2026. "Morphological Variability of Sphenoid Sinus Pneumatization and Its Impact on Adjacent Neurovascular Structures" Diagnostics 16, no. 5: 809. https://doi.org/10.3390/diagnostics16050809
APA StylePapadopoulos-Manolarakis, P., Triantafyllou, G., Georgalas, C., Paschopoulos, I., Stranjalis, G., & Piagkou, M. (2026). Morphological Variability of Sphenoid Sinus Pneumatization and Its Impact on Adjacent Neurovascular Structures. Diagnostics, 16(5), 809. https://doi.org/10.3390/diagnostics16050809

